The Chiefs needed a win in the final match of the regular season to make the top six and keep alive their dream of securing three Super 15 titles in a row.
They did it with a strong defensive effort against a committed Blues outfit who had little to play for but came close to derailing their North Island rivals' campaign.
The win means the Chiefs are definitely in the top six, although they must await the outcome of other matches to determine if they will finish fifth or sixth.
"It was extremely hard work," Chiefs captain Aaron Cruden said. "The boys showed a lot of character.
"There's been a lot of doubters but within our circle we've kept the faith and it's paid off."
While the Chiefs have endured a season marred by inconsistency and poor form, Cruden said they were going into the finals full of confidence after two wins in a row.
"Last week was a step forward and this week is a massive step forward," he said. "There was a bit of fear coming into this game, it could have been the end of the season, but we stuck it out to win."
The Blues went into the game with a mathematical chance of making the finals, needing to beat the Chiefs by at least 38 points.
It was never a realistic prospect, particularly when wind and driving rain prevented them from playing a running game.
They toiled relentlessly in the opening stages, crossing the line three times only to have tries denied when the dogged Chiefs defence held them up and prevented them grounding the ball.
The Chiefs, needing only a win, were content to go into the break leading 3-0 through a Cruden penalty.
The Blues levelled with a Ihaia West penalty just after the restart but the young pivot then gifted the Chiefs a try when Liam Messam intercepted his pass and sprinted away for a five pointer.
The home team narrowed the gap to 11-8 when a period of sustained pressure resulted in a George Moala try.
They
kept up the attack until the final two minutes, when Chiefs prop Ben
Tameifuna won a penalty that allowed his side to wind down the clock and
claim victory.
Scorers:
Chiefs - Try: Liam Messam. Penalties: Aaron Cruden(2) .
Teams:
Blues
15 Charles Piutau, 14 Lolagi Visinia/George Moala, 13 Francis Saili, 12 Ma'a Nonu, 11 Tevita Li, 10 Ihaia West, 9 Bryn Hall, 8 Jerome Kaino, 7 Brendon O'Connor, 6 Steven Luatua, 5 Tom Donnelly, 4 Patrick Tuipulotu, 3 Charlie Faumuina, 2 Keven Mealamu (captain), 1 Sam Pratley
Substittutes: 16 James Parsons, 17 Ofa Tu'ungafasi, 18 Angus Ta'avao, 19 Hayden Triggs, 20 Peter Saili, 21 Jamison Gibson-Park, 22 Jackson Willison, 23 George Moala/Albert Nikoro
Chiefs
15 Tom Marshall, 14 Asaeli Tikoirotuma, 13 Tim Nanai-Williams, 12 Bundee Aki, 11 James Lowe, 10 Aaron Cruden, 9 Tawera Kerr-Barlow, 8 Liam Squire, 7 Tanerau Latimer, 6 Liam Messam, 5 Brodie Retallick, 4 Mike Fitzgerald, 3 Ben Tameifuna, 2 Mahonri Schwalger, 1 Jamie Mackintosh
Substittutes: 16 Nathan Harris, 17 Pauliasi Manu, 18 Nick Barrett, 19 Matt Symons, 20 Tevita Koloamatangi, 21 Augustine Pulu, 22 Gareth Anscombe, 23 Dwayne Sweeney